JPWO2020189331A1 - Torque generator - Google Patents

Abstract

The torque generator of the present invention has a rotor connected to a shaft and capable of rotating around the rotation axis of the shaft, and an external member arranged outside the rotor and rotatably relative to the rotor around the rotation axis. And a magnetic field generating portion that generates a magnetic field that passes through the magnetically responsive material and the magnetically responsive material arranged in the gap between the rotor and the external member, and between the shaft and the external member along the outer periphery of the shaft. It is provided with an adjustment unit provided in. The adjusting unit has an accommodation space provided with an adjustment sealing member inside, and the magnetically responsive material is enclosed in a gap, an accommodation space, and a path connecting these, and the adjustment sealing member is provided in the accommodation space. Is enclosed in the adjustment space from the position where the is provided to the path, and the adjustment unit is capable of changing the volume of the adjustment space according to the volume change of the magnetically responsive material. Therefore, the volume of the space in which the ferrofluid is enclosed can be expanded or contracted by following the expansion and contraction of the volume of the ferrofluid.

Description

The present invention relates to a torque generator capable of varying rotational resistance using a magnetically responsive material.

In the ferrofluid device described in Patent Document 1, a ferrofluid is interposed between two members provided so as to be rotatable relative to each other, and a magnetic field generating portion for applying a magnetic field to the ferrofluid is provided. Further, a sealing material is provided to seal the gap between the shaft and the casing member so that the ferrofluid does not leak out of the main body of the apparatus. Then, a flexible member that operates to expand or contract the volume of the space in which the ferrofluid is enclosed is provided so as to follow the expansion and contraction of the volume of the ferrofluid.

Japanese Unexamined Patent Publication No. 2017-044215

However, in the ferrofluid fluid device described in Patent Document 1, since a flexible member for expanding or contracting the volume of the space in which the ferrofluid fluid is enclosed must be newly provided, the number of parts increases and the number of parts increases. It was necessary to change the manufacturing process.

Therefore, the present invention expands or contracts the volume of the space in which the ferrofluid is enclosed by following the expansion and contraction of the volume of the ferrofluid without increasing the number of parts and significantly changing the manufacturing process. It is an object of the present invention to provide a torque generator capable of providing a torque generator.

In order to solve the above problems, the torque generator of the present invention is connected to a shaft and can rotate around the rotation axis of the shaft, and is arranged outside the rotor and is relative to the rotor around the rotation axis. Along the outer circumference of the shaft, a rotatably provided external member, a magnetically responsive material arranged in a gap between the rotor and the external member, a magnetic field generating portion that generates a magnetic field passing through the magnetically responsive material, and The adjusting portion is provided between the shaft and the external member, the adjusting portion has an accommodating space internally provided with an adjusting sealing member, and the magnetically responsive material is a gap, an accommodating space, and an accommodating space. It is sealed in the path connecting these, and in the accommodation space, it is sealed in the adjustment space from the position where the adjustment sealing member is provided to the path, and the adjustment part adjusts according to the volume change of the magnetically responsive material. The feature is that the volume of the space can be changed.

This allows the space in which the magnetically responsive material is enclosed to respond to the expansion and contraction of the volume of the magnetically responsive material without the addition of new members such as flexible members and without major changes in the manufacturing process. It is possible to provide a torque generator capable of expanding or contracting the volume. Therefore, even if the volume of the magnetically responsive material changes due to a temperature change, a change with time, or the like, a stable and desired resistance force (torque) can be given to the rotor.

In the torque generator of the present invention, it is preferable that the adjusting sealing member can move the adjusting sealing member along the axial direction of the rotating shaft in the accommodation space.
The volume of the adjustment space can be changed by moving the adjustment sealing member in the accommodation space, and the volume of the space in which the magnetic responsive material is enclosed is expanded or contracted according to the expansion and contraction of the volume of the magnetic responsive material. be able to. Further, by providing the torque generator along the axial direction, the accommodation space can be widened without significantly changing the configuration of the torque generator.

In the torque generator of the present invention, it is preferable that the adjustment space is formed between the recess provided in the external member and the outer peripheral surface of the shaft.
Further, it is preferable that the adjustment space is formed between the small diameter portion provided on the shaft and the external member.
As a result, the adjustment space can be changed according to the volume change of the magnetically responsive material without requiring the addition of a new member or a major change in the manufacturing process.

In the torque generator of the present invention, the adjusting sealing member is preferably a ring member having elasticity.
As a result, the adjustment sealing member can be moved in the adjustment space while ensuring the liquidtightness of the adjustment space. Therefore, since the magnetic responsive material can be prevented from flowing out from the adjustment space, the adjustment space can be changed with high accuracy in response to the volume change of the magnetic responsive material.

In the torque generator of the present invention, the rotor is a rotating plate having a surface perpendicular to the rotating shaft, and the external member faces the first bearing portion that supports the shaft so as to be relatively rotatable and one surface of the rotating plate. It is preferable that the adjustment space has a first facing portion and is provided at a position between the first bearing portion and the first facing portion in the axial direction of the rotating shaft.
As a result, the magnetically responsive material can be brought into contact with the rotor over a wide area, so that the control range of the resistance force (torque) applied to the shaft can be widened.

In the torque generator of the present invention, it is preferable that the magnetic field generating unit includes a coil that generates a magnetic field by energization, and the external member includes a first yoke and a second yoke that induce the magnetic field generated by the coil.
As a result, it is possible to form a magnetic circuit through which the magnetic force lines of the magnetic field generated by the magnetic field generating portion flow, and by efficiently and effectively applying the magnetic force lines to the magnetically responsive material, a desired resistance force can be generated.

In the torque generator of the present invention, an adjustment space is provided between the shaft and the first yoke, the first yoke includes a first bearing portion and a first facing portion, and the second yoke is a rotating plate. It is preferable to have a second facing portion facing the other surface.
As a result, the yoke for inducing the magnetic field generated by the magnetic field generating portion can be arranged close to the rotor, and the magnetic force lines can be efficiently passed through the rotor.

In the torque generator of the present invention, the second yoke includes a second bearing portion that rotatably supports the shaft, and the shaft is supported from the outside in the radial direction by the first bearing portion and is supported by the second bearing portion. , It is preferable that the bearing is supported from the axial direction of the rotating shaft.
As a result, it is possible to realize a configuration in which the rotating shaft is stably rotated without adding a new member.

In the torque generator of the present invention, it is preferable that the first facing portion has a thin plate shape.
As a result, the height of the entire device can be kept small.

In the torque generator of the present invention, the external member is a first sealing member having a first bearing portion and a first facing portion, and a first sealing member on the outer peripheral side of the rotating plate with a rotating plate and a gap interposed therebetween. It is preferable to include a second sealing member connected to the.
As a result, the first sealing member and the second sealing member can be joined to each other so as to enclose the magnetically responsive material in the gap between the rotating plate, so that the device can be securely held while holding the magnetically responsive material. It can be disassembled and reused according to the specifications of the device.

In the torque generator of the present invention, the second sealing member includes a second bearing portion that supports the shaft so as to be relatively rotatable, and the shaft is supported by the first bearing portion from the outside in the radial direction and is supported by the second bearing. It is preferable that the portion is supported from the axial direction of the rotating shaft.
As a result, it is possible to realize a configuration in which the rotating shaft is stably rotated without adding a new member.

In the torque generator of the present invention, the magnetic field generating unit includes a coil that generates a magnetic field by energization, and the external member further includes a first yoke that induces a magnetic field generated by the coil, and a rotating plate and a second sealing member. Is preferably made of a magnetic material.
As a result, it is possible to form a magnetic circuit through which the magnetic force lines of the magnetic field generated by the magnetic field generating portion flow, and by efficiently and effectively applying the magnetic force lines to the magnetically responsive material, a desired resistance force can be generated.

In the torque generator of the present invention, the first sealing member is preferably made of a non-magnetic material.
As a result, the influence on the magnetic circuit can be suppressed, so that the resistance force can be efficiently generated.

In the torque generator of the present invention, the shaft is preferably made of a non-magnetic material.
As a result, the magnetic force lines do not pass through the shaft and efficiently enter the outer side of the rotor, so that the control range of the resistance force can be widened.

In the torque generator of the present invention, it is preferable that the accommodation space is formed so that the area in a plan view becomes larger as it approaches the rotor.
As a result, the adjusting sealing member easily moves to the rotor side when the pressure of the magnetic responsive material decreases, so that the position of the adjusting sealing member changes smoothly and quickly with respect to the volume change of the magnetic responsive material. ..

In the torque generator of the present invention, the adjusting sealing member is preferably a ring member having at least a shape that can be elastically deformed along the axial direction of the rotating shaft.
As a result, the adjustment sealing member is elastically deformed in the accommodation space, so that the volume change of the adjustment space can be increased, and the expansion and contraction of the volume of the magnetically responsive material can be compensated.

The ring member consists of two V-rings having a V-shaped cross section perpendicular to the circumferential direction centered on the rotation axis, and each of the above V-shapes is formed from one base end position in the direction along the rotation axis. Two arm-shaped parts extend to the other end position, and the start ends of the two arm-shaped parts are joined to each other at the base end position, and the distance increases in the radial direction toward the end position. Further, it is preferable that the starting ends of the two V-rings are arranged so as to be in contact with or close to each other in the direction along the rotation axis.
As a result, when the volume of the magnetically responsive material is increased or decreased, the adjusting sealing member can easily move in the axial direction.

The adjusting unit preferably includes a ventilation unit that allows outside air to flow in and out of the accommodation space.
As a result, the air in the adjustment space can be released to the outside only when the pressure in the adjustment space becomes higher than a predetermined value, and the pressure can be maintained below a certain value.

According to the present invention, the volume of the space in which the ferrofluid is enclosed can be expanded or contracted by following the expansion and contraction of the volume of the ferrofluid without increasing the number of parts and significantly changing the manufacturing process. A torque generator can be provided.

(A) is a perspective view of the torque generator according to the first embodiment of the present invention as viewed from above, and (b) is a perspective view of the torque generator of (a) as viewed from below. (A) is a cross-sectional view showing a schematic configuration of the torque generator according to the first embodiment, and (b) is a functional block diagram showing a control system of the torque generator according to the first embodiment. It is an exploded sectional view of the torque generator shown in FIG. 2 (a). It is explanatory drawing which conceptually shows the magnetic field generated by the exciting coil in the torque generator shown in FIG. It is a partially enlarged view of FIG. 2 (a). It is sectional drawing which partially enlarged the schematic structure of the torque generator which concerns on the modification. It is sectional drawing which shows the schematic structure of the torque generator which concerns on 2nd Embodiment. FIG. 7 is an exploded cross-sectional view of the torque generator shown in FIG. 7. It is explanatory drawing which conceptually shows the magnetic field generated by the exciting coil in the torque generator shown in FIG. 7. It is a partially enlarged view of FIG. (A) is a cross-sectional view showing a schematic configuration of a torque generator according to a third embodiment, (b) is a partially enlarged view including a shaft 210a in (a), and (c) is a shaft 210b in (a). It is a partially enlarged view including. It is sectional drawing along the rotation axis which shows the structure of the torque generator which concerns on 4th Embodiment. (A) is a cross-sectional view along the rotation axis showing the configuration of the shaft, (b) is a cross-sectional view taken along the line CC'of (a), and (c) is a cross-sectional view taken along the line DD'of (a). It is a figure. (A) and (b) are views showing the structure of the V ring as an adjustment sealing member, (a) is a plan view, and (b) is a cross-sectional view taken along the line BB'of (a). .. (A), (b), and (c) are cross-sectional views showing an enlarged view of the shaft, the guide portion, the ventilation portion, the accommodation space, the two V-rings, and the adjustment space. (A) is a partially enlarged view of FIG. 15 (c), and (b) is a cross-sectional view showing a state after air has flowed out from the adjustment space to the outside.

Hereinafter, the torque generator according to the embodiment of the present invention will be described in detail with reference to the drawings.
<First Embodiment>
FIG. 1A is a perspective view of the torque generator 10 according to the first embodiment as viewed from above, and FIG. 1B is a perspective view of the torque generator 10 as viewed from below. FIG. 2A is a cross-sectional view showing a schematic configuration of the torque generator 10, and FIG. 2B is a functional block diagram showing a control system of the torque generator 10. FIG. 2A is a cross-sectional view taken along the line AA'of FIG. 1A. FIG. 3 is an exploded cross-sectional view of the torque generator 10 shown in FIG. 2 (a). FIG. 4 is an explanatory diagram conceptually showing the magnetic field generated by the exciting coil 20 in the torque generator 10 shown in FIG. 3 with arrows. FIG. 5 is a partially enlarged view of FIG. 2 (a).

In each figure, for convenience of explanation, the vertical direction is defined along the rotation axis AX, but the direction in actual use is not limited. The direction along the rotation axis AX is referred to as an axial direction or a vertical direction, and the direction orthogonal to the rotation axis AX from the rotation axis AX is referred to as a radial direction. In the following description, a state in which the lower side is viewed from the upper side along the rotation axis AX may be referred to as a plan view.

As shown in FIG. 2A, the torque generator 10 includes a holding unit 11 and an operating unit 12. The operation unit 12 includes a shaft 50 and a magnetic disc 80, and is supported by a holding unit 11 so as to be rotatable in both directions around the rotation shaft AX of the shaft 50. The operating portion 12 is supported by the holding portion 11 in a rotatable state via the first bearing portion 34c and the second bearing portion 43 (see FIG. 5). The holding portion 11 includes a first yoke 30 including a first bearing portion 34c, a second yoke 40 including a second bearing portion 43, a third yoke 70, an annular member 21, and an exciting coil 20 as a magnetic field generating portion. .. The first yoke 30, the second yoke 40, the third yoke 70, and the annular member 21 constitute an external member.

<Shaft 50, magnetic disk 80>
The shaft 50 is made of a non-magnetic material and includes a columnar base portion 51 having a constant diameter and a large diameter portion 52 provided at the lower end portion of the base portion 51 in the axial direction so as to have a diameter larger than that of the base portion 51. ..

A magnetic disk 80 as a rotor is fixed to the bottom surface of the shaft 50 (the bottom surface of the large diameter portion 52). The magnetic disk 80 is arranged so that its central axis coincides with the rotation axis AX, and its upper surface 81 and lower surface 82 are perpendicular to the rotation axis AX. The magnetic disk 80 is a rotating plate that can rotate around the rotating shaft AX together with the shaft 50.
At the center of the lower surface 82 of the magnetic disk 80, a protrusion 84 projecting downward is provided.

<External member>
An external member is arranged on the outside of the magnetic disk 80. The outside of the magnetic disk 80 includes the upper side of the upper surface 81 in the vertical direction, the lower side of the lower surface 82, and the outer side of the outer peripheral edge 83 in the radial direction.

The external member includes a first yoke 30, a second yoke 40, a third yoke 70, and an annular member 21, the first yoke 30 is arranged so as to cover the upper side of the magnetic disk 80, and the second yoke 40 is The third yoke 70 is arranged below the magnetic disk 80 so as to cover the upper side of the first yoke 30 and the radial outside of the magnetic disk 80. The first yoke 30, the second yoke 40, and the third yoke 70 are made of, for example, iron or steel and have a magnetic material.

<First yoke 30 (external member)>
The first yoke 30 includes an annular portion 31 and a cylindrical portion 32 integrally provided so as to extend upward from the upper surface of the annular portion 31 concentrically with the annular portion 31. The annular portion 31 and the cylindrical portion 32 have a circular shape centered on the rotation axis AX in a plan view, and the outer diameter of the annular portion 32 is smaller in the cylindrical portion 32 than in the annular portion 31. Due to the difference in outer diameter between the annular portion 31 and the cylindrical portion 32, the step portion 33 is formed on the outer side of the outer peripheral surface of the cylindrical portion 32.

The first yoke 30 has a central hole portion 34 having a circular shape in a plan view with the rotation axis AX as the center and into which the shaft 50 can be inserted. The central hole portion 34 includes a first hole portion 34a and a second hole portion 34b having different inner diameters from each other along the direction of the rotation shaft AX via the first bearing portion 34c. The first bearing portion 34c is provided at substantially the same position as the step portion 33 in the axial direction.

The first hole portion 34a has an inner diameter substantially the same as the diameter of the base portion 51 of the shaft 50. The second hole portion 34b has an inner diameter larger than that of the large diameter portion 52 so as to form a storage space 61 (FIGS. 2A and 5) between the second hole portion 34b and the large diameter portion 52 of the shaft 50. It is a recess of an external member that is recessed radially outward from the first hole 34a.

When the shaft 50 is inserted into the central hole portion 34, the stepped portion between the base portion 51 and the large diameter portion 52 abuts on the first bearing portion 34c, so that the shaft 50 is supported from the outside in the radial direction by the first bearing portion 34c. And it can rotate relative to the first yoke 30.

The lower surface of the first yoke 30 is formed as a first facing surface 35 as a first facing portion facing the upper surface 81 of the magnetic disk 80. The first facing surface 35 is formed so as to extend in the radial direction from the position of the second hole portion 34b of the central hole portion 34 to the position corresponding to the outer peripheral edge 83 of the magnetic disk 80.

<Second yoke 40 (external member)>
The second yoke 40 has a substantially disk shape and is arranged below the lower surface 82 of the magnetic disk 80. The upper surface of the second yoke 40 is formed as a second facing surface 41 as a second facing portion facing the lower surface 82 of the magnetic disk 80. Therefore, the first facing surface 35 as the first facing portion faces one surface (upper surface 81) of the magnetic disk 80, and the second facing surface 41 as the second facing portion faces the other surface (lower surface 82). do.

A second bearing portion 43 that receives the protrusion 84 of the magnetic disk 80 is provided at the center of the second yoke 40 in the radial direction. Although simplified in each figure, the second bearing portion 43 is a recess recessed downward from the second facing surface 41 corresponding to the shape of the protrusion 84, or a hole portion that penetrates the second yoke 40 vertically. It is preferable to have. The shaft 50 and the magnetic disk 80 are supported in the axial direction by the protrusion 84 of the magnetic disk 80 being supported by the second bearing 43.

<Third yoke 70 (external member)>
The third yoke 70 includes an upper wall portion 71 that covers the first yoke 30 and is in contact with the upper surface of the first yoke 30, and a side wall portion 72 that extends downward from the outer circumference of the upper wall portion 71. The plan view shape of the upper wall portion 71 may be, for example, a circle in addition to the rectangle as shown in FIGS. 1 (a) and 1 (b).

The third yoke 70 has a substantially cylindrical through hole 73 in the region including the rotation axis AX (FIG. 2A). The through hole 73 penetrates the third yoke 70 in the vertical direction. As shown in FIG. 2A, the space in the through hole 73 communicates vertically with the space surrounded by the central hole portion 34 of the first yoke 30, and the shaft 50 can be inserted.

Further, a radial outer edge portion 42 of the second yoke 40 is connected to the inner surface of the side wall portion 72 of the third yoke 70. As a result, the magnetic disk 80 is sandwiched between the first yoke 30 and the second yoke 40, and the outer side in the radial direction is surrounded by the third yoke 70.

<annular member 21 (external member)>
In the radial direction, an annular member 21 made of a non-magnetic member and forming an annular shape is arranged between the first yoke 30 and the side wall portion 72 of the third yoke 70. The annular member 21 has a circular shape having substantially the same outer diameter as the exciting coil 20 arranged on the stepped portion 33 in a plan view. The annular member 21 is made of a non-magnetic material such as a thermosetting material, and is between the first yoke 30 and the third yoke 70 in the radial direction and between the exciting coil 20 and the second yoke 40 in the axial direction. Is fixed to. As shown in FIG. 5, the lower surface 22 of the annular member 21 is arranged so as to form the same height as the first facing surface 35 of the first yoke 30 in the axial direction.

As shown in FIGS. 2A and 5, the upper surface 81 of the magnetic disk 80 is separated from the first facing surface 35 of the first yoke 30 and the lower surface 22 of the annular member 21, while the outer peripheral edge 83 is the third yoke. It is separated from the side wall portion 72 of 70. Further, the lower surface 82 of the magnetic disk 80 is also arranged so as to be separated from the second facing surface 41 of the second yoke 40, except for the second bearing portion 43.

As a result, the magnetic disk 80 and the first facing surface 35 of the first yoke 30, the annular member 21, the side wall portion 72 of the third yoke 70, and the second facing surface 41 of the second yoke 40 surrounding the magnetic disk 80. A continuous gap S is formed between them. A magnetic viscous fluid 90 as a magnetically responsive material is arranged in this gap S. The gap S may be filled with only the ferrofluid 90, but air may be contained as long as the resistance to the shaft 50 can be secured.

As described above, the shaft 50 is supported from the outside in the radial direction by the first bearing portion 34c of the central hole portion 34, and the magnetic disc 80 fixed to the shaft 50 is rotated by the second bearing portion 43 of the second yoke 40. It is supported in the axial direction of the shaft AX. As a result, the shaft 50 and the magnetic disk 80 can stably rotate relative to the first yoke 30 and the second yoke 40 as external members about the rotation axis AX.

<Magnetic field generator>
An annular exciting coil 20 wound around the rotation axis AX is arranged between the first yoke 30 and the third yoke 70 on the stepped portion 33 of the first yoke 30 in the radial direction. ing. The exciting coil 20 is arranged in the radial direction in a range corresponding to the outer portion of the magnetic disk 80 including the outer peripheral edge 83 of the magnetic disk 80 and the annular member 21. Further, the exciting coil 20 faces the magnetic disk 80 in the axial direction via the first yoke 30 and the annular member 21.

The exciting coil 20 generates a magnetic field as a magnetic field generating unit by energizing from the control unit 25 (FIG. 2B). The control unit 25 controls the magnitude of the current applied to the exciting coil 20, thereby controlling the magnitude of the magnetic field generated by the exciting coil 20. The control unit 25 includes, for example, an energizing unit that energizes the coil, a central processing unit, and a storage device, and is supplied with electric power from a power source and executes a program stored in the storage device in the central processing unit. By performing control.
In addition, in FIG. 2A and FIGS. 3 to 5, the wiring between the control unit 25 and the exciting coil 20 is omitted.

The exciting coil 20 is surrounded by a first yoke 30 and a third yoke 70 from inside and outside in the radial direction, and is surrounded by a second yoke 40 at the bottom and a third yoke 70 at the top. Therefore, the magnetic field generated by the exciting coil 20 is guided through the path formed by the first yoke 30, the second yoke 40, and the third yoke 70, and a magnetic circuit is formed.

When a current is applied to the exciting coil 20, a magnetic field having magnetic force lines indicated by arrows in FIG. 4 is generated, magnetic force lines along the radial direction are generated in the second yoke 40, and the side wall portion 72 of the third yoke 70. Then, magnetic force lines are generated in the vertical direction. Further, in the upper wall portion 71 of the third yoke 70, magnetic force lines in the direction opposite to the magnetic force lines in the second yoke 40 and in the radial direction are generated, and in the first yoke 30, the magnetic force lines in the side wall portion 72 are generated. Magnetic force lines are generated in the direction opposite to that in the vertical direction. As a result, the magnetic force lines pass up and down in the magnetic disk 80.

Here, by arranging the annular member 21, the first yoke 30 and the side wall portion 72 of the third yoke 70 are magnetically separated below the exciting coil 20. Therefore, the magnetic force lines do not pass in the radial direction between them, and the magnetic force lines flow in the vertical direction in the first yoke 30, and the magnetic force lines efficiently cross the magnetic disk 80 in the vertical direction.
When the direction of energization of the exciting coil 20 is reversed, magnetic force lines in the direction opposite to those shown in FIG. 4 are generated.

The magnetic force lines of the magnetic field shown in FIG. 4 pass through the magnetic viscous fluid 90 in the gap S, the magnetic flux in the vertical direction crosses the magnetic disk 80, and the magnetic flux lines in the magnetic viscous fluid 90 along the radial direction. No magnetic flux is generated, or even if it is generated, its magnetic flux density is small.

Here, the magnetic viscous fluid 90 is a substance whose viscosity changes when a magnetic field is applied, and is, for example, a fluid in which particles (magnetic particles) made of a magnetic material are dispersed in a non-magnetic liquid (solvent). .. As the magnetic particles contained in the ferrofluid 90, for example, iron-based particles containing carbon and ferrite particles are preferable. The diameter of the magnetic particles is preferably 0.5 μm or more, more preferably 1 μm or more. For the magnetic viscous fluid 90, it is desirable to select a solvent and magnetic particles so that the magnetic particles are less likely to precipitate due to gravity. Further, the ferrofluid 90 preferably contains a coupling material that prevents the precipitation of magnetic particles.

In the ferrofluid 90, when a current is applied to the exciting coil 20 to generate a magnetic field, the ferrofluid 90 is given a magnetic field along the vertical direction. Due to this magnetic field, the magnetic particles dispersed in the ferrofluid 90 gather along the lines of magnetic force, and the magnetic particles arranged along the vertical direction are magnetically connected to each other to form a cluster. In this state, when a force for rotating the shaft 50 is applied in the direction centered on the rotation axis AX, a shearing force acts on the connected magnetic particles, and a resistance force (torque) is generated by these magnetic particles. Therefore, the operator can feel the resistance as compared with the state where the magnetic field is not generated.

On the other hand, when the magnetic field generated by the exciting coil 20 is not generated, the magnetic particles are dispersed in the solvent. Therefore, when the operator operates the shaft 50, the holding portion 11 rotates relative to the operating portion 12 without receiving a large resistance force.

<Adjustment section>
As shown in FIG. 5, between the second hole portion 34b of the central hole portion 34 of the first yoke 30 and the large diameter portion 52 of the shaft 50, a storage space 61 is formed in a hollow ring along the outer circumference of the shaft 50. It is provided in. In other words, the accommodation space 61 is formed between the outer peripheral surface 52a of the large diameter portion 52 of the shaft 50 and the recess provided in the first yoke 30 which is an external member.

An O-ring 62 (O-ring) as an adjustment sealing member is arranged in the accommodation space 61. The O-ring 62 is a ring member made of an elastic material, and is an inner surface of the accommodation space 61, that is, an inner surface of the second hole portion 34b of the first yoke 30, and an outer circumference of the large diameter portion 52 of the shaft 50. It is in close contact with the surface 52a in a movable state while sliding up and down along the axial direction of the rotation shaft AX.

The accommodation space 61 is connected to the gap S via the connecting portion 64 as a route. The ferrofluid 90 put into the gap S flows into the accommodation space 61 as well as the gap S. Since the O-ring 62 is in close contact with the inner surface in the accommodation space 61, the inflowing ferrofluid 90 stays at the position where the O-ring 62 is provided in the accommodation space 61 and does not flow above this position. ..

Here, the space below the position where the O-ring 62 is provided in the accommodation space 61 is the adjustment space 63. The accommodation space 61 including the adjustment space 63 is provided at a position between the first bearing portion 34c and the first facing surface 35 as the first facing portion in the axial direction. Further, the adjustment space 63 included in the accommodation space 61 is surrounded by the outer peripheral surface 52a of the large diameter portion 52 of the shaft 50, the recess provided in the first yoke 30 which is an external member, and the O-ring 62. It is formed.

The accommodation space 61, the O-ring 62 as the adjustment sealing member, and the adjustment space 63 form an adjustment portion along the outer circumference of the shaft 50. The adjusting portion is formed between the shaft 50 and the external member in the radial direction. By providing such an adjusting portion, the ferrofluid 90 is enclosed in the gap S, the adjusting space 63 in the accommodation space 61, and the connecting portion 64 as a path connecting the gap S and the adjusting space 63. NS.

When the volume of the ferrofluid 90 changes, the O-ring 62 can move up and down in the accommodation space 61 while maintaining the liquidtightness of the adjustment space 63. As a result, the volume of the adjustment space 63 can be changed according to the volume change of the ferrofluid 90. Here, since the accommodation space 61 is provided so as to extend along the rotation axis AX, no new member is added, so that a large change in the manufacturing process is not required, and the volume of the ferrofluid 90 is not required. The volume of the adjustment space 63 in which the ferrofluid 90 is enclosed can be expanded or contracted in a wide range according to the expansion and contraction of the magnetic viscous fluid 90. Therefore, even if the volume of the magnetically responsive material changes due to a temperature change, a change with time, or the like, a stable and desired resistance force (torque) can be given to the rotor.

Further, the adjusting sealing member is not limited to the O-ring 62 (O-ring), and for example, an X-ring can be used. Further, as shown in FIG. 6, instead of the second hole portion 34b and the accommodation space 61 described above, the closer the accommodation space 61'is to the lower side (magnetic disk 80 (rotor) side), the larger the area in the plan view is. When the second hole portion 34b'is formed so as to be such, the olling 62 easily moves downward when the pressure of the ferrofluid 90 decreases, so that the position of the olling 62 with respect to the volume change of the ferrofluid 90 Changes are smooth and quick. Here, FIG. 6 is a partially enlarged cross-sectional view of the schematic configuration of the torque generator according to the modified example, and is a view at a position corresponding to FIG.

<Second Embodiment>
FIG. 7 is a cross-sectional view showing a schematic configuration of the torque generator 100 according to the second embodiment. The torque generator 100 has an outer shape similar to that of the torque generator 10 of the first embodiment, and FIG. 7 is a cross-sectional view at a position corresponding to FIG. FIG. 8 is an exploded cross-sectional view of the torque generator 100 shown in FIG. 7. FIG. 9 is an explanatory diagram conceptually showing the magnetic force lines of the magnetic field generated by the exciting coil 170 in the torque generator 100 shown in FIG. 7 with arrows. FIG. 10 is a partially enlarged view of FIG. 7. In the following description, detailed description of the same configuration, action, and effect as in the first embodiment will be omitted.

As shown in FIG. 7, the torque generator 100 includes a holding unit 101 and an operating unit 102. The operation unit 102 includes a shaft 110 and a magnetic disk 180, and is supported by a holding unit 101 so as to be rotatable in both directions around the rotation shaft AX. The operating portion 102 is supported by the holding portion 101 in a rotatable state via the first bearing portion 124c and the second bearing portion 153 (see FIG. 10). The holding portion 101 includes a first sealing member 120 including a first bearing portion 124c, an inner yoke 130 (first yoke), an outer yoke 140, a second sealing member 150 including a second bearing portion 153, a housing 160, and a housing 160. The exciting coil 170 is provided as a magnetic field generating unit. The first sealing member 120, the inner yoke 130, the outer yoke 140, the second sealing member 150, and the housing 160 constitute an outer member.

<Shaft 110, magnetic disc 180>
The shaft 110 is made of a non-magnetic material and includes a base portion 111, a flange portion 112, a concave portion 113, a large diameter portion 114, and a disk portion 115, which are continuously formed from the upper side to the lower side (FIG. 8). The base portion 111 has a columnar shape having a constant diameter, and the flange portion 112 is formed so as to spread outward from the lower end of the base portion 111 in a flange shape. The recess 113 is provided so as to be recessed inward in the radial direction from the lower surface of the flange portion 112, and is a small diameter portion having a diameter smaller than that of the base portion 111. The large diameter portion 114 is formed from the lower end of the recess 113, and has a columnar shape having the same diameter as the flange portion 112. The disk portion 115 extends outward from the lower end of the large diameter portion 114 and has a disk shape having a diameter larger than that of the large diameter portion 114. Further, a protruding portion 116 projecting downward is provided at the center of the lower surface of the disc portion 115.

A magnetic disk 180 as a rotor is fixed to the outer edge of the disk portion 115 of the shaft 110. The magnetic disk 180 has an annular shape, and its central axis is arranged so as to coincide with the rotation axis AX. The upper surface 181 and the lower surface 182 of the magnetic disk 180 are perpendicular to the rotation axis AX. The magnetic disk 180 is capable of rotating around the rotation shaft AX together with the shaft 110.

<External member>
An external member is arranged on the outside of the magnetic disk 180. The outer side of the magnetic disk 180 includes an upper side of the upper surface 181 in the vertical direction, a lower side of the lower surface 182, and an outer side of the outer peripheral edge 183 in the radial direction.

The outer member includes a first sealing member 120, an inner yoke 130, an outer yoke 140, a second sealing member 150, and a housing 160. The first sealing member 120 is arranged so as to surround the upper side and the radial outer side of the magnetic disk 180, and the inner yoke 130 and the outer yoke 140 are arranged so as to cover the upper side of the first sealing member 120 and the magnetic disk 180. NS. The second sealing member 150 is arranged below the magnetic disk 180. The housing 160 is arranged so as to surround the first sealing member 120, the inner yoke 130, the outer yoke 140, and the outer side of the second sealing member 150, which surround the magnetic disk 180. The first sealing member 120 is made of a non-magnetic material, and the inner yoke 130, the outer yoke 140, the second sealing member 150, and the housing 160 are made of, for example, iron or steel and have a magnetic material. ..

<First sealing member 120 (external member)>
The first sealing member 120 includes a disk portion 121, a cylindrical portion 122, and an annular portion 123. The cylindrical portion 122 is integrally provided so as to extend upward from the upper surface of the thin plate-shaped disc portion 121 concentrically with the disc portion 121. The annular portion 123 is provided so as to extend downward from the outer edge of the disc portion 121. The disk portion 121 and the cylindrical portion 122 have a circular shape centered on the rotation axis AX in a plan view, and the outer diameter thereof of the cylindrical portion 122 is smaller than that of the disk portion 121.

As shown in FIG. 7, the first sealing member 120 has a central hole portion 124 having a circular shape in a plan view around the rotation axis AX and into which the shaft 110 can be inserted. As shown in FIG. 8, the central hole portion 124 includes a first hole portion 124a and a second hole portion 124b having different inner diameters along the direction of the rotation axis AX via the first bearing portion 124c.

The first hole portion 124a has substantially the same inner diameter as the diameter of the base portion 111 of the shaft 110, and the second hole portion 124b has substantially the same inner diameter as the flange portion 112 and the large diameter portion 114 of the shaft 110. As a result, the accommodation space 191 is formed between the second hole portion 124b and the recess 113 of the shaft 110.

When the shaft 110 is inserted into the central hole portion 124, the stepped portion between the base portion 111 and the flange portion 112 abuts on the first bearing portion 124c, so that the shaft 110 is supported from the outside in the radial direction by the first bearing portion 124c. Moreover, it can rotate relative to the first sealing member 120.

As shown in FIG. 10, a gap P1 extending in the axial direction is provided between the cylindrical portion 122 of the first sealing member 120 and the large diameter portion 114 of the shaft 110, and the gap P1 is continuous with the gap P1. 1 A gap P2 extending in the radial direction is provided between the disc portion 121 of the sealing member 120 and the disc portion 115 of the shaft 110.

The disk portion 121 of the first sealing member 120 faces the upper surface 181 of the magnetic disk 180 as the first facing portion, and the lower surface of the disk portion 121 becomes the first facing surface 125 facing the magnetic disk 180. ing.

The annular portion 123 is arranged so as to cover the radial outer side of the magnetic disk 180, and the side wall portion 162 of the housing 160 is arranged on the outer side of the annular portion 123. Therefore, the magnetic disk 180 and the housing 160 are magnetically separated.

<Internal yoke 130 (external member)>
The inner yoke 130 as the first yoke is made of a magnetic material and is arranged above the disk portion 121 of the first sealing member 120 in the axial direction and outside the cylindrical portion 122 in the radial direction. There is. The upper portion of the inner yoke 130 is a disk portion 131 extending in the radial direction above the exciting coil 170. With this configuration, the inner yoke 130 is arranged so as to cover the inside and the upper side of the exciting coil 170.

<External yoke 140 (external member)>
The outer yoke 140 is an annular member arranged outside the inner yoke 130 with the exciting coil 170 interposed therebetween in the radial direction, and is connected to the radial outer end surface of the disk portion 131 of the inner yoke 130. As a result, the inner inner yoke 130 and the outer outer yoke 140 in the radial direction of the exciting coil 170 are magnetically connected via the disk portion 131.

<Second sealing member 150 (external member)>
The second sealing member 150 has a substantially disk shape, and is arranged below the disk portion 115 of the shaft 110 and the magnetic disk 180 fixed to the disk portion 115. The upper surface of the second sealing member 150 is a second facing surface 151 as a second facing portion, and faces the lower surface 182 of the magnetic disk 180.

A second bearing portion 153 that receives the protrusion 116 of the shaft 110 is provided at the center of the second sealing member 150 in the radial direction. The second bearing portion 153 has a concave shape that is recessed downward from the second facing surface 151, corresponding to the shape of the protrusion 116. The shaft 110 and the magnetic disk 180 are supported in the axial direction by the protrusion 116 being supported by the second bearing 153.

<Housing 160 (external member)>
The housing 160 is made of a magnetic material and includes an upper wall portion 161 and a side wall portion 162 extending downward from the outer periphery of the upper wall portion 161. The inner surface (lower surface) of the upper wall portion 161 is fixed in contact with the upper surfaces of the inner yoke 130 and the outer yoke 140, and covers them. The inner surface of the side wall portion 162 is fixed in contact with the outer yoke 140, the outer side surface of the annular portion 123 of the first sealing member 120, and the outer peripheral surface 152 of the second sealing member 150, respectively. A tip locking portion 163 is provided at the lower end of the side wall portion 162. The plan view shape of the upper wall portion 161 may be, for example, a circle in addition to the rectangle as shown in FIGS. 1 (a) and 1 (b).

The housing 160 has a substantially cylindrical through hole 164 in the region including the rotation shaft AX (FIGS. 7 and 8). The through hole 164 penetrates the housing 160 in the vertical direction. The first sealing member 120 is inserted into the through hole 164.

As shown in FIGS. 7 and 8, the housing 160 is assembled to the first sealing member 120, the inner yoke 130, the outer yoke 140, and the exciting coil 170, which are fixed to each other, from the upper side in the axial direction. At the time of assembly, the side wall portion 162 and the tip locking portion 163 of the housing 160 are in a state of extending along the axial direction (solid line in FIG. 8).

Further, the shaft 110 to which the O-ring 192 and the magnetic disk 180 are mounted in advance is inserted into the first sealing member 120, and then the second sealing member 150 is inserted into the housing 160 so as to be located below the shaft 110. To insert. In this state, the shaft 110 and the second sealing member 150 are assembled in the housing 160 by bending the tip locking portion 163 inward in the radial direction (the state of the broken line in FIG. 8) (state in FIG. 7).

By such an assembling step, the magnetic disk 180 is sandwiched from above and below by the inner yoke 130, the outer yoke 140, and the second sealing member 150, and in the radial direction, the annular portion 123 made of a non-magnetic material is formed. Through, it is surrounded by a housing 160.

As shown in FIGS. 7 and 10, the upper surface 181 of the magnetic disk 180 is separated from the first facing surface 125 (disk portion 121) of the first sealing member 120, while the outer peripheral edge 183 is first sealed. It is separated from the annular portion 123 of the member 120. Further, the lower surface 182 is also arranged so as to be separated from the second facing surface 151 of the second sealing member 150.

As a result, the magnetic disk 180, the first facing surface 125 (disk portion 121) of the first sealing member 120, the annular portion 123, the second sealing member 150, and the magnetic disk 180 surrounding the magnetic disk 180 are fixed. A continuous gap S is formed between the shaft 110 and the large diameter portion 114 of the shaft 110. A magnetically viscous fluid 190 as a magnetically responsive material is arranged in this gap S (FIG. 10).

As described above, the shaft 110 is supported from the outside in the radial direction by the first bearing portion 124c of the first sealing member 120, and the magnetic disc 180 fixed to the shaft 110 is the second bearing of the second sealing member 150. It is supported by the portion 153 in the axial direction of the rotating shaft AX. As a result, the shaft 110 and the magnetic disk 180 have the rotating shaft AX with respect to the first sealing member 120, the inner yoke 130, the outer yoke 140, the second sealing member 150, and the housing 160 as external members. It is stable as a center and can rotate relative to each other.
It should be noted that, instead of the procedure of assembling into the housing 160 in order, the shaft 110 to which the O-ring 192 and the magnetic disk 180 are mounted in advance is inserted into the first sealing member 120, and the magnetic viscous fluid 190 is sealed in the gap S. The second sealing member 150 is joined to the annular portion 123 of the first sealing member 120 so as to be integrated with the inner yoke 130, the outer yoke 140, and the housing 160 in which the exciting coil 170 is arranged. It may be a procedure.

<Magnetic field generator>
An annular exciting coil 170 wound around the rotation axis AX is arranged between the inner yoke 130 and the outer yoke 140 on the disk portion 121 of the first sealing member 120 in the radial direction. Has been done. The exciting coil 170 is arranged in a range corresponding to the magnetic disk 180 in the radial direction. Further, the exciting coil 170 faces the magnetic disk 180 in the axial direction via the disk portion 121 of the first sealing member 120.

The exciting coil 170 generates a magnetic field as a magnetic field generating unit by energizing from a control unit similar to the control unit 25 of the first embodiment.

The exciting coil 170 is surrounded by the inner yoke 130 and the outer yoke 140 from the inside and outside in the radial direction, and is surrounded by the disk portion 131 of the inner yoke 130 and the second sealing member 150 from above and below. Further, it is surrounded by the housing 160 from above and below and from the outside in the radial direction. Therefore, the magnetic field generated by the exciting coil 170 is guided through the path (magnetic circuit) formed by the inner yoke 130, the outer yoke 140, the second sealing member 150, and the housing 160.

When a current is applied to the exciting coil 170, a magnetic field having magnetic force lines indicated by arrows in FIG. 9 is generated, magnetic force lines along the radial direction are generated in the second sealing member 150, and the side wall portion 162 of the housing 160 is generated. And in the outer yoke 140, magnetic force lines in the direction along the vertical direction are generated. Further, in the upper wall portion 161 of the housing 160 and the disk portion 131 of the inner yoke 130, magnetic force lines in the direction opposite to the magnetic force lines in the second sealing member 150 and in the radial direction are generated, and further, the inner yoke At 130, magnetic force lines in the direction opposite to the magnetic force lines in the side wall portion 162 of the housing 160 and the outer yoke 140 and in the vertical direction are generated. As a result, the magnetic force lines pass up and down on the magnetic disk 180.

Here, by arranging the annular portion 123 of the first sealing member 120 between the outer peripheral edge 183 of the magnetic disk 180 and the side wall portion 162 of the housing 160, the magnetic disk 180 and the side wall portion 162 are magnetically separated. Therefore, the magnetic force lines do not pass in the radial direction between them, and the magnetic force lines flow in the vertical direction in the inner yoke 130, and the magnetic force lines efficiently cross the magnetic disk 180 in the vertical direction.
When the direction of energization of the exciting coil 170 is reversed, magnetic force lines in the direction opposite to those shown in FIG. 9 are generated.

The magnetic force lines of the magnetic field shown in FIG. 9 pass through the magnetic viscous fluid 190 in the gap S, the magnetic flux in the vertical direction crosses the magnetic disk 180, and the magnetic flux lines in the magnetic viscous fluid 190 along the radial direction. No magnetic flux is generated, or even if it is generated, its magnetic flux density is small.
Here, the magnetic viscous fluid 190 used is the same as that of the first embodiment.

<Adjustment section>
As shown in FIG. 10, a storage space 191 is provided in a hollow annular shape between the second hole portion 124b of the first sealing member 120, which is an external member, and the recess 113 (small diameter portion) of the shaft 110. .. The accommodation space 191 is connected to the gap S through the gaps P1 and P2.

An O-ring 192 (O-ring) as an adjustment sealing member is arranged in the accommodation space 191. The O-ring 192 is made of an elastic material with respect to the inner surface of the accommodation space 191, that is, the inner surface of the second hole portion 124b of the first sealing member 120, and the outer peripheral surface 113a of the recess 113 of the shaft 110. , The rotating shaft AX is in close contact with the rotating shaft AX so as to be slidable up and down along the axial direction.

The ferrofluid 190 put into the gap S flows into the accommodation space 191 not only through the gap S but also through the gaps P1 and P2 as a path. Here, since the O-ring 192 is in close contact with the inner surface in the accommodation space 191, the inflowing ferrofluid 190 stays at the position where the O-ring 192 is provided in the accommodation space 191 and is above this position. Does not flow in.

Here, the space below the position where the O-ring 192 is provided in the accommodation space 191 is the adjustment space 193. The accommodation space 191 including the adjustment space 193 is provided at a position between the first bearing portion 124c and the first facing surface 125 in the axial direction.

The accommodation space 191 and the O-ring 192 as the adjustment sealing member, and the adjustment space 193 form an adjustment portion along the outer circumference of the shaft 110. The adjusting portion is formed between the shaft 110 and the external member in the radial direction.

By providing the adjustment unit as described above, the ferrofluid 190 is provided in the gap S, the adjustment space 193 in the accommodation space 191 and the gaps P1 and P2 as a path connecting the gap S and the adjustment space 193. It is enclosed.

When the volume of the ferrofluid 190 changes, the O-ring 192 can move up and down in the accommodation space 191 while maintaining the liquidtightness of the adjustment space 193. As a result, the volume of the adjustment space 193 can be changed according to the volume change of the ferrofluid 190.
The other configurations, actions, and effects are the same as those in the first embodiment.

<Third Embodiment>
11 (a) is a cross-sectional view showing a schematic configuration of the torque generator 200 according to the third embodiment, (b) is a partially enlarged view of (a) including the shaft 210a, and (c) is (a). It is a partially enlarged view including the shaft 210b. In the first embodiment and the second embodiment, a magnetic disk is used as the rotor, and in this magnetic disk, the magnetic force lines of the magnetic field generated by the exciting coil cross in the direction along the rotation axis AX, but other than this. As the embodiment of the above, the torque generator 200 of the third embodiment can be configured.

In the torque generator 200 according to the third embodiment, two shafts 210a and 210b arranged separately in the upper and lower parts are used, and a rotor provided with an internal yoke 220 and an exciting coil 250 is fixed between these shafts. .. The external member arranged on the outside of the rotor includes an external yoke 230 and a pair of fixing plates 241 and 242.

The two shafts 210a and 210b are made of a non-magnetic material and are integrated with each other via an internal yoke 220 and an exciting coil 250 arranged between them in the axial direction of the rotating shaft AX. The shafts 210a and 210b can rotate around the rotation shaft AX together with the internal yoke 220 and the exciting coil 250. Therefore, the internal yoke 220 and the exciting coil 250 rotate around the rotation shaft AX as a rotor.

The shaft 210a arranged on the upper side in the axial direction includes a shaft portion 211a extending along the axial direction and a disc portion 212a extending in the radial direction from the lower end of the shaft portion 211a. Similarly, the shaft 210b arranged on the lower side in the axial direction includes a shaft portion 211b extending along the axial direction and a disc portion 212b extending in the radial direction from the upper end of the shaft portion 211b.

The inner yoke 220 is made of a magnetic material and is fixed to both ends of a columnar core portion 221 extending in a direction orthogonal to the axial direction and both ends of the core portion 221. , 222b and the like.

The disc portion 212a of the upper shaft 210a is fixed to the upper surface of the two opposing portions 222a and 222b, and the disc portion 212b of the lower shaft 210b is fixed to the lower surface of the two opposing portions 222a and 222b. NS. The radial outer surfaces of the two opposing portions 222a and 222b are formed as outer peripheral surfaces 223a and 223b that form a part of one circle in a plan view, respectively.

The exciting coil 250 as the magnetic field generating portion is wound around the central axis of the columnar core portion 221 (the axis orthogonal to the rotation axis AX).

An outer yoke 230 made of a magnetic material is arranged outside the inner yoke 220 as a rotor in the radial direction. The outer yoke 230 has a hollow cylindrical shape centered on the rotation axis AX, and its inner peripheral surface 231 faces the outer peripheral surfaces 223a and 223b of the two opposing portions 222a and 222b, respectively, via a gap S. doing. A magnetic viscous fluid 290 as a magnetically responsive material is sealed in the gap S.

Fixing plates 241 and 242 made of non-magnetic material are fixed to the upper part and the lower part of the outer yoke 230, respectively. The fixing plates 241 and 242 are disks arranged around the rotation axis AX, and holes 241a and 242a penetrating in the axial direction (thickness direction) are formed at the centers thereof, respectively.

When a current is applied to the exciting coil 250, a magnetic field having magnetic force lines indicated by arrows in FIG. 11 is generated. The magnetic force lines reach the second facing portion 222b from the first facing portion 222a through the core portion 221 and flow from the second facing portion 222b to the outer yoke 230 facing the outer peripheral surface 223b. Further, a magnetic force line toward the first facing portion 222a is generated from the outer yoke 230 facing the outer peripheral surface 223a of the first facing portion 222a. As a result, the magnetic force lines pass in the radial direction in the gap S.

The shaft portion 211a of the shaft 210a is inserted into the hole portion 241a of the upper fixing plate 241, and the shaft portion 211b of the shaft 210b is inserted into the hole portion 242a of the lower fixing plate 242. A storage space 261a is formed between the inner peripheral surface of the hole 241a and the outer peripheral surface 213a (FIG. 11 (b)) of the shaft portion 211a, and the inner peripheral surface of the hole 242a and the outer peripheral surface 213b of the shaft portion 211b ( A storage space 261b is formed between the space and the space (C).

In the upper accommodation space 261a, O-rings 262a similar to those of the first embodiment and the second embodiment are arranged as adjusting sealing members. The O-ring 262a is in close contact with the inner peripheral surface of the hole 241a and the outer peripheral surface 213a of the shaft portion 211a in a state of being slidable up and down along the axial direction. Further, in the lower accommodation space 261b, the same O-ring 262b as in the first embodiment and the second embodiment is arranged as an adjustment sealing member. The O-ring 262b is in close contact with the inner peripheral surface of the hole 242a and the outer peripheral surface 213b of the shaft portion 211b in a state of being slidable up and down along the axial direction.

A gap P21 is provided between the fixed plate 241 and the disk portion 212a facing each other. Similarly, a gap P22 is provided between the fixing plates 242 facing each other and the disk portion 212b. The ferrofluid 290 in the gap S is arranged in a space connected to the adjustment spaces 263a and 263b in the accommodation spaces 261a and 261b up to the O-rings 262a and 262b through the gaps P21 and P22.

The upper accommodation space 261a, the O-ring 262a, and the adjustment space 263a, and the lower accommodation space 261b, the O-ring 262b, and the adjustment space 263b form an adjustment portion along the outer periphery of the shafts 210a and 210b. NS. The adjusting portion is formed between the shafts 210a and 210b and the external member in the radial direction.

Here, if the accommodation spaces 261a and 261b are configured to have recesses in one of the shafts 210a and 210b and the fixing plates 241 and 242 as in the first embodiment and the second embodiment, the O-rings 262a and 262b This is preferable because the range of movement can be reliably regulated.

When the volume of the ferrofluid 290 changes due to the provision of the adjustment unit as described above, the O-rings 262a and 262b maintain the liquidtightness of the adjustment spaces 263a and 263b in the accommodation spaces 261a and 261b, respectively. While doing so, you can move up and down. As a result, the volume of the adjustment space 263a and 263b can be changed according to the volume change of the ferrofluid 290.
The other configurations, actions, and effects are the same as those in the first embodiment or the second embodiment.

<Fourth Embodiment>
FIG. 12 is a cross-sectional view taken along the rotating shaft AX showing the configuration of the torque generator 300 according to the fourth embodiment, and FIG. 13 (a) is a cross-sectional view taken along the rotating shaft AX showing the configuration of the shaft 350. (B) is a cross-sectional view taken along the line CC'of (a), and (c) is a cross-sectional view taken along the line DD'of (a). 14 (a) and 14 (b) are views showing the configuration of the V ring 362b as the adjusting sealing member, (a) is a plan view, and (b) is a cross section taken along the line BB'of (a). It is a figure. 15 (a), (b), and (c) are enlarged cross-sectional views showing the shaft 350, the guide portion 313, the ventilation portion 314, the accommodation space 361, the two V-rings 362a and 362b, and the adjustment space 363. Is. FIG. 15A is a partially enlarged view of FIG. 12, showing the initial state of the volume of the ferrofluid 390. FIG. 15B shows a state in which the volume of the ferrofluid 390 increases and the two V-rings 362a and 362b are displaced upward until they abut on the lower surface of the guide portion 313. FIG. The volume of the viscous fluid 390 is further increased, and the two V-rings 362a and 362b are contracted to a position beyond the predetermined position P3 (FIG. 16A). 16 (a) is a partially enlarged view of FIG. 15 (c), and FIG. 16 (b) is a cross-sectional view showing a state after air has flowed out from the adjustment space 363.

As shown in FIG. 12, the torque generator 300 includes a holding unit 311 and an operating unit 312. The operation unit 312 includes a shaft 350 and a magnetic disk 380, and is supported by a holding unit 311 so as to be rotatable in both directions around the rotation shaft AX of the shaft 350. The operating portion 312 is supported by the holding portion 311 in a rotatable state via the guide portion 313 and the bearing portion 343. The holding portion 311 includes a guide portion 313, a first yoke 330, a second yoke 340 including a bearing portion 343, a third yoke 370, an annular member 321 and an exciting coil 320 as a magnetic field generating portion. The guide portion 313, the first yoke 330, the second yoke 340, the third yoke 370, and the annular member 321 constitute an external member.

<Shaft 350, Magnetic disk 380>
The shaft 350 is made of a non-magnetic material and has a substantially columnar shape. As shown in FIG. 12 or FIG. 16A, the shaft 350 includes a range corresponding to the guide portion 313 in the axial direction among the portions inserted into the holding portion 311 and includes the bottom surface 313a of the guide portion 313. A notch 356 is formed up to a predetermined position P3 in the accommodation space 361 with the upper limit of the above. As shown in FIG. 13C, the cutout portion 356 is a cutout of a part of the outer peripheral surface 355 and forms a plane along the axial direction. The shaft 350 has an outer peripheral surface 355 having a circular shape in a plan view at the lower base portion 351 of the predetermined position P3 (see FIGS. 13A, 13B, and 13C). At the predetermined position P3, a step portion 357 is formed as a displacement portion that displaces the outer diameter of the shaft 350 by providing the notch portion 356. Further, a flange portion 352 protruding in the radial direction is provided below the base portion 351, and a protruding portion 353 protruding downward is provided in the radial center portion of the flange portion 352.

As shown in FIG. 12, a magnetic disk 380 as a rotor is fixed to the outer peripheral surface of the protrusion 353 at the bottom of the shaft 350. The magnetic disk 380 is arranged so that its central axis coincides with the rotation axis AX, and its upper surface 381 and lower surface 382 are perpendicular to the rotation axis AX. The magnetic disc 380 is a rotating plate that can rotate around the rotating shaft AX together with the shaft 350, and can be rotated by a bearing portion 343 provided in the center of the second yoke 340 located below the magnetic disc 380. It is supported.

<External member>
An external member is arranged on the outside of the magnetic disk 380. The outside of the magnetic disk 380 includes the upper side of the upper surface 381 and the lower side of the lower surface 382 in the vertical direction, and the outer side of the outer peripheral edge 383 in the radial direction.

The external member includes a guide portion 313, a first yoke 330, a second yoke 340, a third yoke 370, and an annular member 321 (FIG. 12). The guide portion 313 is arranged so that its inner peripheral surface 313b faces the outer peripheral surface of the shaft 350, and the first yoke 330 and the third yoke 370 are arranged outside the guide portion 313. The first yoke 330 is arranged so as to cover the upper side of the magnetic disk 380, and the second yoke 340 is arranged so as to cover the lower side of the magnetic disk 380 and the radial outer side of the first yoke 330. The third yoke 370 is arranged so as to cover the upper side of the first yoke 330 and the second yoke 340. The guide portion 313 is made of a non-magnetic material, and the first yoke 330, the second yoke 340, and the third yoke 370 are made of, for example, iron or steel and have a magnetic material.

<Guide unit 313 (external member)>
As shown in FIG. 12, the guide portion 313 is a cylindrical member having an inner peripheral surface 313b having an inner diameter corresponding to the outer peripheral surface 355 of the shaft 350. In the guide portion 313, the inner peripheral surface 313b and the outer peripheral surface 355 of the shaft 350 are arranged so as to be in contact with each other, whereby the shaft 350 is rotatably supported by the guide portion 313 and rotates relative to the external member. It will be possible.

In the guide portion 313, at the portion of the shaft 350 facing the notch portion 356, a ventilation portion 314 is formed between the guide portion 313 and the shaft 350 as a gap extending along the axial direction. The upper side of the ventilation portion 314 is connected to the outside in the axial direction, and the lower side in the axial direction is connected to the accommodation space 361. Therefore, the accommodation space 361 is connected to the outside through the ventilation portion 314.

<First yoke 330 (external member)>
As shown in FIG. 12, the first yoke 330 includes an annular portion 331 and a cylindrical portion 332, and a stepped portion 333 is formed on the outer side of the outer peripheral surface of the cylindrical portion, similarly to the first yoke 30 of the first embodiment. Will be done.

The first yoke 330 has a central hole portion 334 having a circular shape in a plan view with the rotation axis AX as the center and into which the guide portion 313 can be inserted. A guide portion 313 is inserted into the central hole portion 334 at an upper portion up to a substantially intermediate position in the axial direction, and a storage space 361 is formed between the central hole portion 334 and the shaft 350 below the bottom surface 313a of the guide portion 313. There is.

Similar to the first embodiment, the lower surface 330a of the first yoke 330 is a first facing portion facing the upper surface 381 of the magnetic disk 380, and is a position corresponding to the outer peripheral edge 383 of the magnetic disk 380 in the radial direction. It is formed by spreading to.

<Second yoke 340 (external member)>
The second yoke 340 includes a bottom wall portion 341 having a substantially disk shape in a plan view, and a side wall portion 342 extending axially upward from the peripheral edge portion of the bottom wall portion 341. The bottom wall portion 341 is arranged below the lower surface 382 of the magnetic disk 380, and the side wall portion 342 is arranged so as to cover the first yoke 330, the annular member 321 and the exciting coil 320 from the radial outside. The upper surface of the bottom wall portion 341 faces the lower surface 382 of the magnetic disk 380 as the second facing portion. Therefore, one surface (upper surface 381) of the magnetic disk 380 faces the lower surface 330a of the first yoke 330 as the first facing portion, and the other surface (lower surface 382) faces the bottom wall portion as the second facing portion. The upper surfaces of 341 face each other.

A bearing portion 343 that supports the shaft 350 is provided at the center of the second yoke 340 in the radial direction, and the magnetic disk 380 fixed to the shaft 350 is also rotatably supported.

<Third yoke 370 (external member)>
As shown in FIG. 12, the third yoke 370 has a substantially disk shape, and is arranged so as to cover the first yoke 330 and the side wall portion 342 of the second yoke 340 from above.

The third yoke 370 has a substantially cylindrical through hole 371 that penetrates vertically in the region including the rotation axis AX. The through hole 371 communicates with the central hole portion 334 of the first yoke 330 in the vertical direction. A guide portion 313 is inserted and fixed in the through hole 371, and a shaft 350 is further inserted inside the guide portion 313.

<annular member 321 (external member)>
As shown in FIG. 12, in the radial direction, an annular member 321 made of a non-magnetic member and forming an annular shape is arranged between the first yoke 330 and the side wall portion 342 of the second yoke 340. The annular member 321 has a circular shape having substantially the same outer diameter as the exciting coil 320 arranged on the step portion 333 in a plan view. The annular member 321 is fixed between the first yoke 330 and the second yoke 340 in the radial direction by a thermosetting material or the like which is a non-magnetic material. A material having appropriate elasticity may be used as the annular member 321 and pressure-welded arrangement may be performed between the first yoke 330 and the second yoke 340.

Here, in the magnetic disk 380, the upper surface 381 is separated from the lower surface 330a of the first yoke 330 and the lower surface 321a of the annular member 321 while the outer peripheral edge 383 is separated from the side wall portion 342 of the second yoke 340. .. Further, the lower surface 382 of the magnetic disk 380 is also arranged so as to be separated from the bottom wall portion 341 of the second yoke 340.

As a result, a continuous gap S is formed between the magnetic disk 380, the lower surface 330a of the first yoke 330, the lower surface 321a of the annular member 321 and the second yoke 340 surrounding the magnetic disk 380. A magnetic viscous fluid 390 as a magnetically responsive material is arranged in this gap S. The gap S may be filled with only the ferrofluid 390, but air may be contained as long as the resistance to the shaft 350 can be secured.

As described above, the shaft 350 is supported from the outside in the radial direction by the inner peripheral surface 313b of the guide portion 313, and is supported in the axial direction of the rotating shaft AX by the bearing portion 343 of the second yoke 340. As a result, the shaft 350 and the magnetic disk 380 are stably relative to the guide portion 313, the first yoke 330, the second yoke 340, and the third yoke 370 as external members about the rotation axis AX. It becomes rotatable.

<Magnetic field generator>
As shown in FIG. 12, it is wound around the rotation axis AX on the stepped portion 333 of the first yoke 330 and between the first yoke 330 and the side wall portion 342 of the second yoke 340 in the radial direction. An annular exciting coil 320 is arranged. The exciting coil 320 is arranged in the radial direction in a range corresponding to the outer portion of the magnetic disk 380 including the outer peripheral edge 383 of the magnetic disk 380 and the annular member 321. Further, the exciting coil 320 faces the magnetic disk 380 in the axial direction via the first yoke 330 and the annular member 321. The control and operation of the exciting coil 320 is the same as that of the exciting coil 20 of the first embodiment.

The exciting coil 320 is surrounded from inside and outside in the radial direction by the side wall portions 342 of the first yoke 330 and the second yoke 340, and below, the annular portion 331 of the first yoke 330 and the bottom wall portion 341 of the second yoke 340. Above, it is surrounded by a third yoke 370. Therefore, the magnetic field generated by the exciting coil 320 is guided through the path formed by the first yoke 330, the second yoke 340, and the third yoke 370 to form a magnetic circuit.

When a current is applied to the exciting coil 320, a magnetic field having magnetic force lines is generated, and the first yoke 330, so as to surround the exciting coil 320, as in the case of the first embodiment shown in FIG. A magnetic force line is generated that passes through the second yoke 340 and the third yoke 370 in order. Here, the point that the first yoke 330 and the side wall portion 342 of the second yoke 340 are magnetically separated below the exciting coil 320 by arranging the annular member 321 is also the same as in the first embodiment. be.

The magnetic force lines of the magnetic field generated by the exciting coil 320 pass through the magnetic viscous fluid 390 in the gap S, and the magnetic flux in the vertical direction crosses the magnetic disk 380. The magnetic viscous fluid 390 uses the same substance as the magnetic viscous fluid 90 of the first embodiment.

When a magnetic field along the vertical direction is applied to the magnetic viscous fluid 390, the dispersed magnetic particles gather along the lines of magnetic force and line up along the vertical direction, as in the case of the magnetic viscous fluid 90 of the first embodiment. When the magnetic particles are magnetically connected to each other to form a cluster and a force is applied to rotate the shaft 350 in the direction centered on the rotation axis AX, a shearing force acts on the connected magnetic particles, and these Resistance (torque) is generated by magnetic particles. Therefore, the operator can feel the resistance as compared with the state where the magnetic field is not generated. Further, when the magnetic field generated by the exciting coil 320 is not generated, the magnetic particles are dispersed in the solvent, and when the operator operates the shaft 350, the holding unit 311 does not receive a large resistance force and is placed on the operating unit 312. It rotates relative to the relative.

<Adjustment section>
As shown in FIG. 15A, the outer peripheral surface of the shaft 350 is between the first yoke 330 and the shaft 350 in the radial direction and between the guide portion 313 and the flange portion 352 of the shaft 350 in the axial direction. The accommodation space 361 is provided in a hollow annular shape along the above. The inner wall of the accommodation space 361 includes a step portion 357 of the shaft 350, and the position of the step portion 357 in the axial direction is a specification for ventilation from the accommodation space 361 and two V rings 362a and 362b to be accommodated. It is determined according to the elasticity and shape of the wall.

Two V-rings 362a and 362b as adjusting sealing members are arranged in the accommodation space 361. The V-rings 362a and 362b are ring members made of an elastic material, and have the same shape although they have different orientations. Taking the V ring 362b arranged on the lower side as an example, as shown in FIG. 14A, the V ring 362b is an annulus centered on the rotation axis AX, and the annulus is an annulus in a plan view. The circumferential direction D1 is defined so as to follow the outer shape of. As shown in FIG. 14B, the V-ring 362b is orthogonal to the circumferential direction D1 and has a V-shaped cross section including the rotation axis AX. The V-shape of the V-ring 362b is from one base point position P11 (upper surface position in FIG. 14 (b)) in the direction along the rotation axis AX to the other end position P12 (lower surface position in FIG. 14 (b)). The two arm-shaped portions A11 and A12 have a shape in which they extend respectively. At the base point position P11, the two arm-shaped portions A11 and A12 are joined to each other at the start end portion As, and the distance between the two arm-shaped portions A11 and A12 increases in the radial direction toward the end position P12. The basic feature of this shape is the same for the V-ring 362a arranged on the upper side. The two V-rings 362a and 362b are arranged so as to be upside down and overlapped in the direction along the rotation axis AX so that the base point position P11 is proximal to each other. That is, the upper V-ring 362a is arranged in a V-shape with the upper side open in the direction along the rotation axis AX, and the lower V-ring 362b is arranged in an inverted V-shape with the lower side open. The starting ends As of the two V-rings 362a and 362b are arranged in contact with or close to each other in the direction along the rotation axis AX. When the two V-rings 362a and 362b are in contact with each other, the shape formed by the cross section of the two V-rings 362a and 362b orthogonal to the circumferential direction D1 and including the rotation axis AX is X-shaped. As a result, the two V-rings 362a and 362b are arranged so that their V-shapes open as they are separated from each other along the axial direction of the rotation axis AX.

The two V-rings 362a and 362b can be elastically deformed along the axial direction of the rotation axis AX and along the radial direction depending on the shape and the physical properties of the constituent materials. For example, in the state shown in FIG. 15A, the lower 362b is in contact with both the inner peripheral surface 335 of the first yoke 330 and the outer peripheral surface 355 of the shaft 350 in the radial direction due to elastic deformation.

In the following description, the fact that the two V-rings 362a and 362b are in contact with the surrounding members means that they are in close contact with each other so as to be slidable and movable up and down while blocking the passage of gas and liquid.

As shown in FIGS. 15A, 15B, and 15C, the accommodation space 361 is connected to the gap S via the connecting portion 364 as a route. In the initial state shown in FIGS. 15A and 12, the gap S is filled with the ferrofluid 390, and the connection portion 364 and the accommodation space 361 are filled with air. The ferrofluid 390 placed in the gap S can flow into the accommodation space 361 through the connecting portion 364 as well as the gap S.

Of the accommodation space 361, the space below the position where the lower V ring 362b is provided is the adjustment space 363. When the volume of the ferrofluid 390 changes, the pressure of the air inside the connection portion 364 and the adjustment space 363 increases or decreases. Therefore, the two V-rings 362a and 362b are integrally moved up and down by the pressure change of the air inside the connecting portion 364 and the adjusting space 363, and the upper end position of the adjusting space 363 is moved up and down according to the up and down. From the initial state shown in FIG. 15 (a), when the pressure of the air in the adjustment space 363 increases due to the volume increase of the ferrofluid 390, as shown in FIG. 15 (b), two due to the increased pressure of the air. The V-rings 362a and 362b are pushed upward. When the pressure of the air in the adjustment space 363 further increases, as shown in FIGS. 15 (c) and 16 (a), the two V-rings 362a and 362b abut on the bottom surface 313a of the guide portion 313 and contract vertically. However, the lower V-ring 362b is located above the predetermined position P3 corresponding to the step portion 357. In consideration of the volume of the adjustment space 363 and the elasticity and shape of the two V-rings 362a and 362b, the magnetic viscous fluid 390 has an optimum amount of air inside the connection portion 364 and the adjustment space 363. The filling amount can be adjusted.

The upper part of the accommodation space 361 is connected to the ventilation portion 314, and the accommodation space 361, the two V-rings 362a and 362b, the adjustment space 363, and the ventilation portion 314 provide an adjustment portion along the outer periphery of the shaft 350. It is composed. As a result, the accommodation space 361 is connected to the outside air through the ventilation portion 314, and the two V-rings 362a and 362b are more than the stepped portion 357 (predetermined position P3) of the shaft 350 as the volume of the ferrofluid 390 increases. When located above, air can flow in and out between the adjustment space 363 and the outside via the vent 314 (FIGS. 15 (c) and 16 (a)).

As shown in FIGS. 15A and 15B, at least in a state where the lower V-ring 362b is in elastic contact with the first yoke 330 and the shaft 350, the air in the adjustment space 363 is on the lower side. The V-ring 362b suppresses the outflow into the accommodation space 361 above the adjustment space 363.

As shown in FIG. 16A, when the two V-rings 362a and 362b are located above the predetermined position P3 corresponding to the step portion 357 due to the increase in the volume of the ferrofluid 390, the lower part is below. A gap G is formed between the V ring 362b on the side and the stepped portion 357 of the shaft 350. Due to the shape of the notch 356 and the stepped portion 357, the elasticity of the two V-rings 362a and 362b, and the viscosity of the ferrofluid 390, the air from the adjustment space 363 in the gap G (FIG. 16A). The distance between the stepped portion 357 and the lower V-ring 362b is defined so that the two-dot chain line) can flow out and the ferrofluid 390 does not flow out above P3. As a result, the increased pressure in the adjustment space 363 can be reduced. Further, after the pressure drops, as shown in FIG. 16B, the two V-rings 362a and 362b recover from the contracted state, and the lower V-ring 362b is displaced below the step portion 357. Therefore, the outflow of air to the outside is stopped and the desired pressure can be maintained.
The other configurations, actions, and effects are the same as those in the first embodiment.

In the fourth embodiment, the shaft 350 is provided with the notch portion 356, but instead of this, the first yoke 330 may be provided with the notch portion recessed outward in the radial direction. Further, instead of these, a through hole connecting to the outside is provided in the shaft 350 or the first yoke 330, and the outlet of the through hole is provided at the predetermined position P3 so that the two V rings 362a and 362b are in the predetermined positions. The air in the adjustment space 363 may be allowed to flow out when the position exceeds P3.
Further, similarly to the ventilation portion 314 in the fourth embodiment, in the configurations of the first embodiment, the second embodiment, the third embodiment, and the modified examples thereof, the ventilation portion is provided between the shaft and the external member. It is also possible.
Although the present invention has been described with reference to the above-described embodiment, the present invention is not limited to the above-described embodiment, and can be improved or modified within the purpose of improvement or the idea of the present invention.

As described above, the torque generator according to the present invention encloses the ferrofluid in accordance with the expansion and contraction of the volume of the ferrofluid without increasing the number of parts and without significantly changing the manufacturing process. It is useful in that the volume of the created space can be enlarged or reduced.

10, 100, 200, 300 Torque generator 11, 101, 311 Holding unit 12, 102, 312 Operation unit 20, 320 Exciting coil (magnetic field generator)
21 Ring member (external member)
22 Bottom surface 25 Control unit 30 First yoke (external member)
31 Annulus 32 Cylindrical part 33 Step part 34 Central hole part 34a First hole part 34b, 34b'Second hole part 34c First bearing part 35 First facing surface 40 Second yoke (external member)
41 Second facing surface 42 Outer edge 43 Second bearing 50 Shaft 51 Base 52 Large diameter 52a Outer peripheral surface 61, 61'Accommodation space 62 O-ring (O-ring, adjustment sealing member)
63 Adjustment space 64 Connection (path)
70 Third yoke (external member)
71 Upper wall part 72 Side wall part 73 Through hole 80 Magnetic disc (rotor)
81 Upper surface 82 Lower surface 83 Outer peripheral edge 84 Protrusions 90, 190, 290 Ferrofluid (magnetically responsive material)
110 Shaft 111 Base 112 Flange 113 Recess 113a Outer peripheral surface 114 Large diameter 115 Disc 116 Protrusion 120 1st sealing member 121 Disk 122 Cylindrical 123 Circular 124 Central hole 124a 1st hole 124b 2 holes 124c 1st bearing 125 1st facing surface 130 Internal yoke 131 Disk 140 External yoke 150 2nd sealing member 151 2nd facing surface 152 Outer peripheral surface 153 2nd bearing 160 Housing 161 Upper wall 162 Side wall Part 163 Tip locking part 164 Through hole 170 Exciting coil 180 Magnetic disk 181 Top surface 182 Bottom surface 183 Outer peripheral edge 191 Storage space 192 O-ring (O-ring, adjustment sealing member)
193 Adjustment space 210a, 210b Shaft 211a, 211b Shaft 212a, 212b Disc 213a, 213b Outer surface 220 Inner yoke 221 Core part 222a, 222b Opposing part 223a, 223b Outer surface 230 External yoke 231 Inner peripheral surface 241a, 242a Hole Parts 241 and 242 Fixed plate 250 Exciting coil 261a, 261b Accommodation space 262a, 262b O-ring (O-ring, adjustment sealing member)
263a, 263b Adjustment space 313 Guide part (external member)
313a Bottom surface of guide part 313b Inner peripheral surface of guide part 314 Ventilation part 321 Ring member (outer member)
321a Lower surface of annular member 330 First yoke (external member)
330a Lower surface of the first yoke 331 Ring part 332 Cylindrical part 333 Step part 334 Central hole part 335 Inner peripheral surface of the first yoke 340 Second yoke (external member)
341 Bottom wall part 342 Side wall part 343 Bearing part 350 Shaft 351 Base part 352 Flange part 353 Protrusion part 355 Outer peripheral surface 356 Notch part (displacement part)
357 Stepped part (displaced part)
361 Storage space 362a, 362b V ring (adjustment sealing member)
363 Adjustment space 364 Connection (path)
370 Third yoke (external member)
371 Through hole 380 Magnetic disc (rotor)
381 Upper surface of magnetic disk 382 Lower surface of magnetic disk 383 Outer peripheral edge of magnetic disk 390 Magnetic viscous fluid (magnetically responsive material)
G Gap P1, P2, P21, P22 Gap P3 Predetermined position S Gap AX Rotation axis

Claims (19)

A rotor that is connected to the shaft and can rotate around the rotation axis of the shaft,
An external member arranged outside the rotor and rotatably provided relative to the rotor about the rotation axis,
A magnetically responsive material arranged in the gap between the rotor and the external member,
A magnetic field generator that generates a magnetic field that passes through the magnetically responsive material,
An adjusting portion provided between the shaft and the external member is provided along the outer circumference of the shaft.
The adjusting portion has an accommodating space having an adjusting sealing member inside.
The magnetically responsive material is enclosed in the gap, the accommodation space, and the path connecting them, and in the accommodation space, the adjustment sealing member is enclosed in the adjustment space from the position where the adjustment sealing member is provided to the path. Has been
The adjusting unit is a torque generator characterized in that the volume of the adjusting space can be changed according to the volume change of the magnetically responsive material. The torque generating device according to claim 1, wherein the adjusting unit is the torque generating device according to claim 1, wherein the adjusting sealing member can move along the axial direction of the rotating shaft in the accommodating space. The torque generating device according to claim 2, wherein the adjusting space is formed between a recess provided in the external member and an outer peripheral surface of the shaft. The torque generator according to claim 2, wherein the adjustment space is formed between a small diameter portion provided on the shaft and the external member. The torque generator according to any one of claims 1 to 4, wherein the adjusting sealing member is an elastic ring member. The rotor is a rotating plate having a surface perpendicular to the rotating axis.
The external member has a first bearing portion that supports the shaft so as to be relatively rotatable, and a first facing portion that faces one surface of the rotating plate.
The torque according to any one of claims 1 to 5, wherein the adjusting space is provided at a position between the first bearing portion and the first facing portion in the axial direction of the rotating shaft. Generator. The magnetic field generating unit includes a coil that generates a magnetic field when energized.
The torque generator according to claim 6, wherein the external member includes a first yoke and a second yoke that induce a magnetic field generated by the coil. The adjustment space is provided between the shaft and the first yoke.
The first yoke includes the first bearing portion and the first facing portion.
The torque generator according to claim 7, wherein the second yoke has a second facing portion facing the other surface of the rotating plate. The second yoke includes a second bearing portion that supports the shaft so as to be relatively rotatable.
The torque generator according to claim 8, wherein the shaft is supported from the outside in the radial direction by the first bearing portion and is supported from the axial direction of the rotating shaft by the second bearing portion. The torque generator according to claim 6, wherein the first facing portion has a thin plate shape. The external member is formed on the first sealing member on the outer peripheral side of the rotating plate with the first sealing member including the first bearing portion and the first facing portion, the rotating plate, and the gap interposed therebetween. The torque generator according to claim 10, further comprising a second sealing member to be connected. The second sealing member includes a second bearing portion that supports the shaft so as to be relatively rotatable.
The torque generator according to claim 11, wherein the shaft is supported from the outside in the radial direction by the first bearing portion and is supported from the axial direction of the rotating shaft by the second bearing portion. The magnetic field generating unit includes a coil that generates a magnetic field when energized.
The external member further comprises a first yoke that induces a magnetic field generated by the coil.
The torque generator according to claim 12, wherein the rotating plate and the second sealing member are made of a magnetic material. The torque generator according to claim 13, wherein the first sealing member is made of a non-magnetic material. The torque generator according to any one of claims 1 to 14, wherein the shaft is made of a non-magnetic material. The torque generator according to any one of claims 1 to 15, wherein the accommodation space is formed so that the area in a plan view becomes larger as it approaches the rotor. The torque generating device according to claim 1 or 2, wherein the adjusting sealing member is at least a ring member having a shape elastically deformable along the axial direction of the rotating shaft. The ring member is composed of two V-rings having a V-shaped cross section orthogonal to the circumferential direction about the rotation axis, and each of the V-shaped groups is one group in the direction along the rotation axis. Two arm-shaped portions extend from the end position to the other end position, and the start ends of the two arm-shaped portions are joined to each other at the base end position. The torque generating device according to claim 17, wherein the starting ends of the two V-rings are arranged so as to be in contact with or close to each other in a direction along the rotation axis. The torque generator according to claim 2, wherein the adjusting unit includes a ventilation unit that allows outside air to flow in and out of the accommodation space.

Images